Organic dye molecules and nonlinear optical polymeric compounds containing chromophores

ABSTRACT

Organic dye molecular materials prepared by coupling existing organic chromophore molecules to benzene or carbazole derivatives and nonlinear optical polymer compounds having polyimide repeating units coupled with the organic dye molecular material are provided. The organic dye molecular material coupled to a polymer main chain in the preparation of the nonlinear optical compound has the following:  
                 
 
     where X 1  is carbon oxygen, sulfur, nitrogen, ester (CO 2 ), or amide (CONR 1 ), where R 1  is an alky or phenyl group having 1 to 6 carbon atoms, D is an organic chromophore molecule, and n is an integer from 1 to 10.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to polymeric compounds withnonlinear optical properties, and more particularly, to organic dyemolecular materials and nonlinear optical polymer compounds containingchromophores.

[0003] 2. Description of the Related Art

[0004] Recently, the development of high-speed, high-capacity datatransmission devices has increased the need for materials that exhibitnonlinear optical properties and research in this field is beingactively performed (Ind. Eng. Chem. Res. 1999, 38, 8-33). Thesenonlinear optical materials are roughly categorized into inorganicmaterials such as LiNbO₃, KHP, quartz and the like, which have beenwidely used, and organic materials which become more interesting in thefield in recent years along with semiconductor materials. Organicmaterials are advantageous over inorganic materials in terms of theirsynthesis and processing procedures and that their physical propertiesincluding the processing temperature, refractive index, nonlinearoptical coefficient, absorption wavelength and the like can be adjustedaccording to the requirements. This is the reason why research on theorganic material becomes increasing in the field (U.S Pat. Nos.5,496,899 and 6,229,047).

[0005] Organic materials are classified into crystalline molecules andpolymeric substances based on their structure. In the early stage ofresearch, many researchers in a variety of fields were very interestedin the crystalline molecule due to its large optical coefficient.However, the crystalline molecule is limited by its unstable nature anddifficulties in the crystal growing and processing. To address theselimitations, approaches to dispersing organic molecules in polymericmedia to develop new materials have been actively made in recent years(Chem. Mater. 1999, 11,1966-1968). The molecular mobility in a polymericmedium reduces thermal stability and molecular aggregation causessignificant optical losses, thereby limiting use of the material.

[0006] Meanwhile, to develop materials with desirable processingproperties of polymers by incorporating nonlinear organic molecules intopolymers is greatly acceptable. Nonlinear polymers are classified intomain chains and side chains depending on the way of molecular coupling.Recently, highly ordered macromolecules coupled to be chemically stable,called dendrimer , have been developed and many approaches have beenmade to increase their applications (U.S. Pat. Nos. 5,659,010,5,496,899, and 6,001,958).

[0007] In another aspect of research, some researchers are involved indeveloping new materials based on covalently-bonded film formationtechnique improved from the Languir-Blodegette (LB) film formationtechnique. Although it is difficult to obtain a thin film having anappropriate thickness for use with this method, the resulting thin filmhas a structure highly ordered to give a very large nonlinearcoefficient.

[0008] For main chain polymers, nonlinear molecular chromophores aredirectly used as molecules to be polymerized so that the synthesis ofthe main chain polymer is difficult and the resulting polymer has poorthree-dimensional orientation efficiency during a poling process. Forside chain polymers, chromophores are grafted to the core as sidechains. In this case, although it is difficult to chemically react thepolymer, the selection of core polymer is flexible and a variety ofchromophores can be incorporated. The ordered arrangement ofchromophores on the polymer chain as its side chains is alsoadvantageous.

[0009] Dendrimers are sterically highly symmetric and exhibit differentcharacteristics according to their functional end groups incorporated.Also, appropriate designing of a dendrimer molecular structure canseparate individual chromophores. When excess chromophores over apredetermined amount are incorporated into a polymeric material,aggregation occurs due to chromophore-chromophore electrostaticinteractions, thereby resulting in a low nonlinearity and opticalscattering loss due to micro domain. Recent studies evidently show thatthese problems can be eliminated by using dendrimers (Appl. Phys. Lett.2000, 77(24), 3881-3883).

[0010] Basically, the development of highly nonlinear materials needshighly nonlinear dye molecules. According to recent research results, anonlinear molecule needs a structure capable of partial electronpolarization and a large dipolar moment to provide a large nonlinearity.It is advantageous that the nonlinear molecule has strong electron donorand electron acceptor end groups. In addition, the nonlinear moleculeshould be extended by conjugated double or triple bonds to allow theelectrons, i.e., the π-electrons, present between the end groups to movefreely. It has been also founded that the nonlinearity effect isincreased when such conjugated linkages are stably present on the sameplane. Some materials with extended π-linkages to increase theirnonlinearity have been reported. As the number of π-linkages increases,the visible light absorption region of the material where electrontransition absorption occurs is gradually shifted to a long-wavelengthregion. This directly affects on the optical loss by absorption, therebylimiting its use as an optical device material (J. Am. Chem. Soc.1999,121, 472-473; Chem. Mater. 1999,11,1966-1968). As an example, awavelength converter or an optical amplifier is often used as a lightsource of a wavelength of about 600-800 nm. Thus, it is necessary todevelop materials that are transparent in this wavelength range for theoptical communication device.

[0011] Meanwhile, the nonlinearity is directly proportional to thechromophore density in a unit volume. As described above, a highchromophore density over a predetermined range results in a reducednonlinearly. Therefore, there is a need to increase the chromophoredensity in a polymeric material without this adverse effect.

SUMMARY OF THE INVENTION

[0012] To solve the above-described problems, it is a first objective ofthe present invention to provide an organic dye molecular materialsuitable for use in the formulation of an optical polymeric compoundhaving a high nonlinearity.

[0013] It is a second objective of the present invention to provide anonlinear optical polymeric compound for use as an optical devicematerial that comprises molecules capable of absorbing ashort-wavelength light, has a high dye molecule density, and isspatially highly ordered to provide a high nonlinearity.

[0014] To achieve the first objective of the present invention, there isprovided an organic dye molecular material having the following formula:

[0015] where X₁ is hydrocarbon, oxygen, sulfur, nitrogen, ester (CO₂),or amide (CONR₁), where R₁ is an alky or phenyl group having 1 to 6carbon atoms, D is an organic chromophore molecule, and n is an integerfrom 1 to 10.

[0016] To achieve the first objective of the present invention, there isprovided another organic dye molecular material the following formula:

[0017] where D is an organic chromophore molecule, and n is an integerfrom 1 to 10.

[0018] In formulae (1) and (2) above, the organic chromophore molecule Dmay be any well-known organic chromophore. For example, the organicchromophore molecule D may have a structure selected from structures(A-1), (A-2) and (A-3) in the following formula (3) in which eachchromophore molecule is shown as D—OH:

[0019] where R and R′ are each independently alkyl or phenyl groupshaving 1 to 10 carbon atoms, A₁ is carbon or nitrogen, X₂ is N0₂, asulfonyl-substituted or unsubstituted alkyl group having 1 to 10 carbonatoms, CN, —C(CN)═C(CN)₂, an ester group, a carbonyl group, a halogenelement, or a haloalkyl group, and n is an integer from 1 to 11.

[0020] In conjunction with formula (3), typical examples of the organicchromophore molecule having the structure (A-1) include Disperse Red 1(DR1) series where R═CH₃CH₂, A₁═N, X₂═NO₂, and n=2, dialkylaminophenylnitrostilbene (DANS) series where R═CH₃CH₂, A₁═CH, X₂═NO₂, and n=2, DASSseries where R═CH₃ or CH₃CH₂, A₁═CH, X₂═SO₂, and n=2, and the like. Atypical example of the organic chromophore molecule having the structure(A-2) includes AIDC derivatives where R═CH₃CH₂, CH₃, or phenyl, X₂═CN,R′═CH₃, and n=2.

[0021] To achieve the second objective of the present invention, thereis provided a nonlinear optical polymeric compound containing polyimiderepeating units to which the organic dye molecular material having theformula (1) or (2) above is coupled.

[0022] It is preferable that the nonlinear optical polymeric compoundaccording to the present invention comprises a polyimide main chainhaving formula (4) or (5) below.

[0023] The nonlinear optical polymeric compound may have a linearhomopolyimide backbone. Alternatively, the nonlinear optical polymericcompound can have a copolymer backbone of polyimide repeating units andother repeating units.

[0024] The nonlinear optical polymeric compound preferably have a numberaverage molecular weight of 5,000-500,000.

[0025] In the nonlinear optical polymer compound according to thepresent invention, the polyimide repeating unit preferably has thefollowing formula:

[0026] where A and B are each independently fluorocarbon-substituted orunsubstituted hydrocarbons having 1 to 4 carbon atoms, oxygen, nitrogen,or sulfur, and m is in the range of 0.01 to 1 as the ratio of thepolyimide repeating units to all the repeating units of the opticalpolymeric compound.

[0027] More preferably, the polyimide repeating unit has the followingformula:

[0028] In the nonlinear optical polymer compound according to thepresent invention, the amount of the organic chromophore molecule Dbeing coupled to the polyimide repeating unit may be flexibly adjusted.Also, the organic chromophore molecule may be composed of one kind oforganic chromophore molecules or different kinds of organic chromophoremolecules in a predetermined ratio. Preferably, the polyimide repeatingunit contains 10-60% by weight of the organic chromophore molecule D.

[0029] According to the present invention, commonly used organicchromophore molecules are coupled into the structure of formula (1) or(2) to give organic dye materials having the new structures. When theorganic dye materials according to the present invention areincorporated into optical polymeric compounds, the amount of dye perunit volume of the polymer compound can be highly increased.

[0030] The nonlinear optical polymeric compound according to the presentinvention meets the optical material requirements as the molecularaggregation caused by electrostatic interactions between dye moleculesdoes not occur in the compound at high dye densities. In addition, theoptical polymeric compound according to the present invention issuitable for use in the manufacture of an easy-to-manufacture devicewith excellent physical and chemical stabilities as well as nonlinearoptical effects.

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The above objectives and advantages of the present invention willbecome more apparent by describing in detail preferred embodimentsthereof with reference to the attached drawings in which:

[0032]FIG. 1 shows the structure of an optical polymeric compoundaccording to a preferred embodiment of the present invention;

[0033]FIG. 2 is a graph showing the thermal stability of a devicemanufactured from the optical polymeric compound according to thepreferred embodiment of the present invention; and

[0034]FIG. 3 is a graph showing the result of an optical characteristicdetermination for a device manufactured from the optical polymericcompound according to the preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0035] The synthesis path of a first embodiment of an organic dyemolecular material according to the present invention is illustrated inScheme (1) as follows. In Scheme (1), reactions to couple an organicchromophore D using benzene derivative are illustrated.

[0036] In Scheme (1), the organic dye molecular material includes theorganic chromophore D reacting with and coupled to the 3- and 5-phenolichydroxyl (—OH) groups of the benzene ring. In forming this structure, analiphatic hydroxyl group is introduced to allow easy incorporation ofthe organic chromophore D into the polymer. In particular, an aliphaticalcohol compound (I) is first synthesized using dihydroxybenzoic acid byesterification, a compound (III) having the alcoholic hydroxyl groupselectively protected as the acetate group is synthesized via tworeaction steps, and an ether-bonded compound (IV) is synthesized usingtriphenylphosphine (PPh₃) and diethyl azodicarboxylate (DEAD) known bythe Mitsunobu reaction. Then, the protected hydroxyl group is recoveredby deprotection reaction to afford a compound (V).

[0037] The synthesis path of a second embodiment of the organic dyemolecular material according to the present invention is illustrated inScheme (2). In Scheme (2), reactions to couple an organic chromophore Dusing a carbazole derivative are illustrated.

[0038] As illustrated in Scheme (2), in coupling the organic chromophoreD using the carbazole derivative, one of the three hydroxyl groups ofthe carbazole derivative is protected as a silicon derivate to couplethe organic chromophore D. Methylsulfonyl groups are incorporated to theother two hydroxyl groups to give a compound (VII) and so as to serve asa leaving group in the following ether bonding reaction. Next, theorganic chromophore D is coupled, followed by desilylation to afford acompound (IX).

[0039] The following Scheme (3) illustrates the synthesis path of anoptical polymeric compound by incorporation of the organic dye molecularmaterial obtained through the reactions illustrated in Scheme 1 or 2into a polyimide backbone.

[0040] In Scheme (3), linear polyimide is used as an optical polymermain chain. To incorporate organic chromophore groups as side chains tothe polyimide main chain, the Mitsunobu reaction is accomplished usingtriphenylphosphine (PPh₃) and diethyl azodicarboxylate (DEAD). Theorganic chromophore D is a well-known organic chromophore with maximumabsorption at 350˜600 nm wavelength.

[0041] The synthesis reactions illustrated in Schemes (1) through (3)will be described in greater detail by means of the following examples.

Example 1 Synthesis of Compound (I)

[0042] To a 1-L-2-neck flask containing 400 mL of benzene was added 31 g(0.2 mol) of 3,5-dihydroxybenzoic acid, 71 g (0.6 mol) of 1,6-hexanediol, and 1.9 g (10 mmol) toluene sulfonic acid as a catalyst, and themixture was vigorously stirred. The reactor was equipped with aDean-Stark apparatus and the benzene was refluxed for about 6 hourswhile raising the temperature of the reactor using a thermal coil toremove water. After sufficiently removing the benzene, the organicfraction was dissolved with ethylether, neutralized with aqueous sodiumhydrogencarbonate, and washed several times with water. The remainingwater was removed from the organic fraction using magnesium sulfate,followed by concentration to obtain a white solid compound. Theresulting solid compound was recrystallized using benzene to yield3,5-dihydroxybenzoic acid ester (I) (47 g, 92%).

[0043]¹H—NMR (400 MHz; solvent: CDCl₃/acetone-d6; δ ppm): 8.26 (d, 2H,—OH), 6.96 (s, 2H), 6.52 (t, 1H), 4.17 (t, 2H), 3.55 (br, 2H), 3.07 (br,1H, —OH), 1.6 (m, 2H), 1.52 (m, 2H), 1.38 (m, 4H)

[0044]³C—NMR (solvent: CDCl₃/acetone-d6; δ ppm): 166.3, 158.0, 132.1,108.0, 107.3, 64.7, 62.1, 32.4, 28.4,25.7, 25.3

Example 2 Synthesis of Compound (II)

[0045] The 3,5-dihydroxybezoic acid ester (I) obtained from Example 1was treated with acetic anhydride and triethylamine to protect all thehydroxyl groups as the acetyl groups, affording Compound (II).

Example 3 Synthesis of Compound (III)

[0046] 19 g (0.05 mol) of Compound (II) obtained from Example 2 wasdissolved in 150 mL methanol. 6.5 g (0.1 mol) of Zn powder activatedwith 10% -HCl was added to the solution and stirred vigorously for 12hours at room temperature. The Zn powder was separated by filtration andthe solvent was removed. The resulting product mostly included Compound(III) and a small amount of Compound (I) produced as a result of sidereaction. The resulting product may be directly subjected to the nextreaction if necessary. In the present example, the resulting product waspurified by chromatography on silica gel to remove the by-product,resulting in a high-purity Compound (III).

Example 4 Synthesis of Compound (IV)

[0047] To couple the organic chromophore to the Compound (III) obtainedfrom Example 3, ester bonding was accomplished using the well-knownMitsunobu reaction. 3.0g (10 mmol) of the Compound (III), the organicchromophore (AIDC) having the structure (A-2) of formula (3) above,where R and R′ are CH₃, X₂ is CN, and n=2, and 5.8 g (22 mmol) oftriphenylphosphine (PPh₃) were dissolved in 50 mL anhydroustetrahydrofuran (THF). 3.5 mL (22 mol) of diethylazodicarbonate (DEAD)was added slowly over 10 minutes while stirring in a nitrogenatmosphere. The mixture was left at room temperature for about 1 hourand concentrated until the volume was reduced to about 1/3, and theconcentrate was dropped into ethyl ether to precipitate any residue toyield a red ether solution.

Example 5 Synthesis of Compound (V)

[0048] The red ether solution obtained from Example 4 was concentratedand dissolved in a mixture of 30 mL methanol and 15 mL THF. 3 g (22mmol) of grounded potassium carbonate was added to the mixture,vigorously stirred, and left at room temperature for 2 hours. Theresulting solution was concentrated, dissolved in 100 mL ethylether, andwashed with 200 mL water. The resulting organic fraction wasconcentrated again, dissolved in about 10 mL anhydrous THF, andrecrystallized using 150 mL methanol. The resulting precipitate wasfiltered and dried in a vacuum to yield Compound V (DAIDC) with a 88%yield.

[0049]¹H—NMR (400 MHz; solvent: CDCl₃; δ ppm): 7.37 (d, 4H), 7.1 (d,2H), 6.99 (d, 2H), 6.75 (d, 2H), 6.69 (m, 5H), 6.55 (t, 2H), 4.25 (t,2H), 4.13 (t, 4H), 3.78 (t, 4H), 3.60 (t, 2H), 3.09 (s, 6H), 2.49 (s,4H), 2.40 (s, 4H), 1.73 (m, 2H), 1.55 (m, 2H), 1.22 (m, 4H), 1.02 (s,12H)

[0050]¹³C—NMR (solvent: CDCl₃; δ ppm): 169.1, 166.0, 159.4, 155.2,150.0, 137.8, 132.3, 129.4, 124.4, 123.8, 121.3, 114.1, 113.3, 111.9,107.8, 106.2, 75.6, 65.5, 65.1, 62.5, 51.3, 42.8, 39.1, 39.0, 32.4,31.8, 28.5, 27.9, 25.6, 25.3

Example 6 Synthesis of Optical Polymeric Compound

[0051] An optical polyimide was synthesized using the polyimide mainchain illustrated in Scheme (3) and the organic chromophore (DAIDC)obtained from Example 5 as follows. 1 g of the linear polyimide actingas the main chain for a optical polymeric compound, 3 g (3.3 mmol) ofthe organic chromophore (DAIDC) and 0.88 g (3.3 mmol) oftriphenylphosphine (PPh₃) was added to and dissolved in 35 mL anhydrousTHF in a nitrogen atmosphere while stirring for 30 minutes. 0.58 g ofdiethylazodicarbonate (DEAD) was added slowly to the mixture at roomtemperature and stirred for about 3 hours. 0.44 g of PPh₃ and 0.29 g ofDEAD were further added and stirred at room temperature for 10 hours.The reaction product was slowly poured into a mixture of 100 mL methanoland 50 mL water to precipitate a polymeric material. The precipitate wasfiltered and dried. The dried product was dissolved in 25 g of THF andprecipitated again using 200 mL methanol. These precipitation andfiltration were repeated two times more. The resulting optical polymericmaterial was vacuum dried at 70

C for 24 hours to yield dark red powder (3.5 g, 92%).

[0052] The maximum UV absorption spectrum of the resulting product wasobserved at 510 nm and the glass transition temperature (Tg) observed bydifferential scanning calorimetry (DSC) was 153

0 C.

Example 7 Determination of Optical Polymeric Compound Characteristics

[0053] 1 g of the optical polymeric material obtained from Example 6 wasdissolved in 20 g of a cyclohexanone solvent for about 10 hours toobtain a 15% solution by weight. This solution was passed through aporous filter layer having a 0.2-μm pore size to remove all smallparticles. The resulting solution was spin casted on an indium tin oxide(ITO) glass substrate at 1000 rpm for 30 seconds and vacuum dried at 150

C for 10 hours, resulting in an optical polymer film of a thickness ofabout 2 mm. An upper surface of the optical polymer film was vacuumdeposited with gold (Au) to a thickness of 0.1 μm to form an upperelectrode. The resulting sample device formed of the optical polymericcompound according to the present invention was determined for thermalstability and optical characteristics.

[0054]FIG. 1 shows the structure of the optical polymeric compoundaccording to the present invention used in an optical characteristicdetermination, which will be described below.

[0055]FIG. 2 shows the result of a thermal stability test for theoptical polymeric compound having the structure of FIG. 1, which wasperformed on the sample formed in Example 7. For the thermal stabilitytest of the optical polymeric compound having the structure of FIG. 1,variations in electro-optic (EO) coefficient with time were determinedat different temperatures. Here, the optical polymeric compound used toform the sample had a glass transition temperature of about 153

C. As is apparent from FIG. 2, the EO coefficient was stably maintainedat a temperature of 80

C after a gentle reduction.

[0056]FIG. 3 shows the result of an optical characteristic determinationfor the optical polymeric compound having the structure of FIG. 1, whichwas performed on the sample formed in Example 7. The organic chromophoreD incorporated into the optical polymeric compound having the structureof FIG. 1 is AIDC having the structure (A-2) of formula (3), where R andR′ are CH₃, X₂ is CN, and n=2. As described above, an organic dyemolecular material of formula (1) above was synthesized from the organicchromophore D having the structure (A-2) and coupled to a polyimide mainchain to give an optical polymer compound (PEI-DAIDC). Then, thisoptical polymer compound was used to form the sample of Example 7.

[0057] For comparison in the optical characteristic determination, acontrol sample was formed in the same manner as in Example 7 except thatan optical polymeric compound (PEI-AIDC) synthesized by coupling theorganic chromophore having the structure (A-2) to a polyimide mainchain, as described with reference to Scheme (3), was used.

[0058] For the sample of Example 7 according to the present inventionand the control sample, a variety of polymeric compounds weresynthesized by varying the amount of the organic chromophore D beingincorporated into each polymeric compound, and the EO coefficients ofthe polymeric compounds were measured for variations in organicchromophore content. As a result, the EO coefficient was obviouslyincreased with increased amount of the organic chromophore D. Incomparing the polymeric compounds PEI-AIDC (control sample) andPEI-DAIDC (present invention), PEI-DAIDC exhibits better nonlinearitythan PEI-AIDC at the same organic chromophore contents. It is obviousfrom this result that the structure of the organic dye molecularmaterial according to the present invention advantageously affects theoptical characteristics.

[0059] The organic dye molecular material according to the presentinvention is derived from the coupling of existing organic chromophoresto benzene or carbazole derivatives. Also, the optical polymericcompound according to the present invention includes polyimide repeatingunits to which the organic dye molecular material according to thepresent invention is coupled. In the structure of the optical polymericcompound according to the present invention, the organic dye molecularmaterial is chemically stably coupled to the polymer main chain.Therefore, the molecular aggregation caused by electrostaticinteractions between dye molecules does not occur at high dye densities,which meets the optical material requirements. In addition, the drawbackof dendrimers can be improved by substitution of dendrimer-structuredmolecules into polymers. By adjusting the number of side chains as theorganic dye molecular material according to the present invention,physical properties of the resulting optical polymeric compound can bevaried so that devices with desired properties can be easilymanufactured.

[0060] In the optical polymeric compound according to the presentinvention, a variety of dye molecules, which are well known in the art,are arranged to be spatially efficient to give a high nonlinearity. Theoptical polymeric compound according to the present invention can absorba short wavelength of light without having a long π-electron covalentbond length and thus it exhibits a higher nonlinearity than theconventional optical polymeric compound with directly dye-substitutedside chains, at similar dye contents. The structure of the organic dyemolecular material according to the present invention is advantageousfor optical characteristic improvements.

[0061] By adjusting the hydrocarbon chain length of the organic dyemolecular material being coupled into an optical polymeric compoundaccording to the present invention, the glass transition temperature ofthe optical polymeric compound that is an important consideration in themanufacture of optical devices can be controlled. The optical polymericcompound according to the present invention is suitable for use in themanufacture of an easy-to-manufacture device with excellent physical andchemical stabilities as well as nonlinear optical effects.

[0062] While this invention has been particularly shown and describedwith reference to preferred embodiments thereof, it will be understoodby those skilled in the art that various changes in form and details maybe made therein without departing from the spirit and scope of theinvention as defined by the appended claims.

What is claimed is:
 1. An optical polymeric compound containingpolyimide repeating units to which an organic dye molecular materialhaving the following formula is coupled:

where X₁ is hydrocarbon, oxygen, sulfur, nitrogen, ester (CO₂), or amide(CONR₁), where R₁ is an alky or phenyl group having 1 to 6 carbon atoms,D is an organic chromophore molecule, and n is an integer from 1 to 10.2. The optical polymeric compound of claim 1, wherein the organicchromophore molecule D has a structure selected from the followingformula (A-1), (A-2) and (A-3) in which each chromophore molecule isshown as D—OH:

where R and R′ are each independently alkyl or phenyl groups having 1 to10 carbon atoms, A₁ is carbon or nitrogen, X₂ is NO₂, asulfonyl-substituted or unsubstituted alkyl group having 1 to 10 carbonatoms, CN, —C(CN)═C(CN)₂, an ester group, a carbonyl group, a halogenelement, or a haloalkyl group, and n is an integer from 1 to
 11. 3. Theoptical polymeric compound of claim 1, having a homopolyimide backbone.4. The optical polymeric compound of claim 1, wherein the polyimiderepeating unit has the following formula:

where A and B are each independently fluorocarbon-substituted orunsubstituted hydrocarbons having 1 to 4 carbon atoms, oxygen, nitrogen,or sulfur, and m is in the range of 0.01 to 1 as the ratio of thepolyimide repeating units to all the repeating units of the opticalpolymeric compound.
 5. The optical polymeric compound of claim 4,wherein the polyimide repeating unit has the following formula:


6. The optical polymeric compound of claim 4, wherein the polyimiderepeating unit contains 10-60% by weight the organic chromophoremolecule D.
 7. The optical polymeric compound of claim 4, wherein thepolyimide repeating unit is coupled with at least one organicchromophore molecule selected from the group of organic chromophoremolecules having the following formula (A-1), (A-2) and (A-3) in whicheach chromophore molecule is shown as D—OH, or with a combination of theorganic chromophore molecules in a predetermined ratio:

where R and R

are each independently alkyl or phenyl groups having 1 to 10 carbonatoms, A₁ is carbon or nitrogen, X₂ is NO₂, a sulfonyl-substituted orunsubstituted alkyl group having 1 to 10 carbon atoms, CN,—C(CN)═C(CN)₂, an ester group, a carbonyl group, a halogen element, or ahaloalkyl group, and n is an integer from 1 to 11.